JPH07273015A - Treatment method - Google Patents

Abstract

PURPOSE:To improve throughput by effectively using a treatment solution. CONSTITUTION:A developing solution feeding pipe 26 and a rinsing solution feeding pipe 27 are connected to a feeding nozzle 22 through a confluent pipe 24. After a linsing solution R has been fed to the surface of a semiconductor wafer W on which a circuit pattern is transferred, a developing solution D is fed, the developing solution D and the rinsing solution R are mixed before the feeding of the developing solution is finished, and the mixture is fed to the semiconductor wafer W. After feeding of the mixture of the developing solution and the rinsing solution, the rinsing solution R is fed to the semiconductor wafer W. As a result, a liquid film of rinsing solution R is formed on the surface of the semiconductor wafer W, and the expansion of the developing solution D can be facilitated. Also, the amount of consumption of the developing solution D can be decreased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a processing method for subjecting an object to be processed such as a semiconductor wafer to development processing.

[0002]

2. Description of the Related Art Generally, in a semiconductor device manufacturing process, a series of processes in which a semiconductor wafer is coated with a photoresist, a circuit pattern is reduced by using a photolithography technique and transferred to the photoresist, and the photoresist is developed. Is applied.

In the above developing process, a developing solution as a treating solution is supplied to the semiconductor wafer having the circuit pattern transferred thereon, and after the developing process, a cleaning solution (rinsing solution) for washing away the developing solution of the semiconductor wafer to clean the surface is supplied. ing. In this case, when the resist that is insoluble due to the exposure process contains the developer, its volume increases (swells), and the swelled resist contracts due to the rinsing liquid to cause stress, which causes a bridge between circuit patterns. There was a problem.

Therefore, conventionally, there is known a developing system in which a developing solution and a rinsing solution are mixed and supplied to a wafer for the purpose of alleviating the phenomena of swelling and shrinking (Japanese Patent Laid-Open No. 61-279).
858). The developing method disclosed in Japanese Patent Application Laid-Open No. 61-279858 is such that the developing solution is supplied to the wafer at the same time while the mixing ratio of the developing solution and the rinsing solution is made inversely proportional, and the developing processing is performed.

[0005]

By the way, for example, a polyimide-based resist solution has a high viscosity as compared with a general resist solution, and the film thickness is as thick as 10 μm as compared with a typical resist having a thickness of 1 μm. In some cases, the conventional developing method requires a lot of time for the developing process, resulting in a decrease in throughput. In order to solve this problem, it is conceivable to increase the supply amount of the developing solution, but even if the developing solution is increased, the effect is not so great, and there is a problem that the consumption amount of the developing solution and the rinse solution increases. is there.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a processing method capable of improving the throughput by effectively using the processing liquid.

[0007]

In order to achieve the above object, the first treatment method of the present invention is premised on a treatment method in which a treatment liquid is supplied to a treatment object on which a circuit pattern is transferred and treatment is performed. A pretreatment step of supplying a cleaning liquid to the object to be processed, a treatment step of supplying the processing liquid to the object to be treated after supplying the cleaning liquid, and a treatment liquid and a cleaning solution before the end of the supply of the processing liquid And a second post-treatment step of supplying a cleaning liquid to the object to be treated after supplying a mixed liquid of the treatment liquid and the cleaning liquid. It is a feature (Claim 1).

The second processing method of the present invention is based on the processing method of supplying the processing liquid to the object to which the circuit pattern is transferred and performing the processing, as in the first processing method. A pretreatment step of supplying a cleaning liquid to the object to be treated, a treatment step of supplying the treatment liquid to the object to be treated by starting the supply of the cleaning liquid before the supply of the cleaning liquid, and a treatment liquid before the end of the supply of the treatment liquid. A first post-processing step of mixing a cleaning liquid with a cleaning liquid and supplying the cleaning liquid to the object to be processed, and a second post-processing step of supplying a cleaning liquid to the object to be processed after supplying the mixed liquid of the processing liquid and the cleaning liquid. And (2).

In the second treatment method, the treatment liquid may be instantaneously supplied within the time when the supply of the cleaning liquid and the supply of the treatment liquid in the treatment process overlap each other, or the treatment liquid is gradually increased to a predetermined amount. It may be increased (claim 3).

Further, in the first post-treatment step of the treatment method of the present invention, the supply of the treatment liquid may be stopped instantaneously, or the supply of the treatment liquid may be gradually reduced (claim 4). . In the first post-treatment step, the cleaning liquid may be supplied instantaneously, or the cleaning liquid may be gradually supplied (claim 5). Furthermore, the first
In the subsequent post-treatment step, the supply of the treatment liquid may be gradually decreased and the supply of the cleaning liquid may be gradually increased (claim 6).

[0011]

According to the processing method of the present invention by the above technical means, the cleaning film is supplied before the processing liquid is supplied to the object to which the circuit pattern is transferred, so that the liquid film is formed on the surface of the object. To promote the spread of the processing liquid,
The processing time can be shortened. Further, by mixing and replacing the treatment liquid and the cleaning liquid, it is possible to alleviate the swelling and shrinkage of the resist of the circuit pattern formed on the object to be treated (claim 1).

Further, the concentration of the treatment liquid can be gradually increased by gradually increasing the treatment liquid to a predetermined amount within the time when the supply of the cleaning liquid and the supply of the treatment liquid in the treatment process overlap. Uniformity can be achieved (claim 2).

[0013]

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings. In this embodiment, a case where the processing apparatus according to the present invention is applied to a semiconductor wafer processing system will be described.

As shown in FIG. 1, a semiconductor wafer (hereinafter referred to as wafer) processing system includes a loader unit 1 for loading and unloading a wafer W as an object to be processed, a brush cleaning device 2 for cleaning the wafer W with a brush, A jet water cleaning device 3 for cleaning the wafer W with high-pressure jet water, an adhesion processing device 4 for hydrophobicizing the surface of the wafer W, and an electronic cooling means such as a Peltier element utilizing the Peltier effect cools the wafer W to a predetermined temperature. Cooling processing device 5, resist coating device 6 having a function of coating resist on the surface of wafer W and removing excess resist on the peripheral portion of the wafer by side rinse treatment, heating wafer W before and after resist coating and prebaking In addition, the heat treatment device 7 for performing post-baking, the exposed wafer W is developed, and the circuit pattern after development is rinsed. Processing apparatus according to the present invention having a function of physical collectively the like (developing apparatus) 8 so as to improve work efficiency.

A wafer transfer path 9 is provided along the longitudinal direction at the center of the processing system configured as described above, and the devices 2 to 8 are arranged on the wafer transfer path 9 with their front faces facing each other. Wafer transfer mechanism 11 including a wafer transfer arm 10 for transferring the wafer W to and from each of the devices 2 to 8.
Are provided movably along the wafer transfer path 9.
Then, for example, one unprocessed wafer W stored in a wafer cassette (not shown) of the loader unit 1 is taken out and conveyed, and cleaning, adhesion processing, cooling, resist coating, prebaking, and exposure (not shown) are performed in this order. After exposure by the apparatus, after development processing by the developing apparatus 8 according to the present invention, post-baking is performed, and the processed wafer W is transferred and stored in a wafer cassette (not shown) of the loader unit 1.

As shown in the schematic diagram of FIG. 2, the developing device 8 includes a spin chuck 20 for adsorbing and holding a wafer W by a vacuum device (not shown) and horizontally rotating the wafer W, and a wafer holding portion of the spin chuck 20. It comprises a processing cup 21 arranged so as to surround it, and a supply nozzle 22 for supplying a processing liquid such as a developing liquid and a cleaning liquid such as a rinse liquid such as pure water onto the wafer W. In this case, the spin chuck 20 is configured to be movable in the vertical direction by driving an elevator cylinder (not shown) connected to the rotation shaft 23. Further, the processing cup 21 is also configured to be movable in the vertical direction by an elevator cylinder (not shown).

A merging pipe 24 for supplying the developing solution and the rinsing liquid is connected to the supply side of the supply nozzle 22, and the developing solution supply pipe 26 is connected to the merging pipe 24 via a three-way switching valve 25.
And a rinse liquid supply pipe 27 are connected. The developing solution supply pipe 26 is connected to a developing solution tank 28 that contains the developing solution D. The developing solution supply pipe 26 has a filter 29 and a mass flow controller 30 in this order from the three-way switching valve 25 toward the developing solution tank 28. A flow meter 31 is provided.
Further, a supply source 34 of an inert gas such as nitrogen (N2) is connected to the developer tank 28 via a regulator 32 and a filter 33, and the addition by the N2 gas supplied from the N2 gas supply source 34 is performed. Developer tank 2 by pressure
The developer D in 8 is sent to the supply nozzle 22 and supplied onto the wafer W. The rinse liquid supply pipe 27 is connected to a rinse liquid tank 35 that stores the rinse liquid R. The rinse liquid supply pipe 27 has a three-way switching valve 2
5 to the rinse liquid tank 35 in order from the filter 3
6, a mass flow controller 37, and a flow meter 38 are provided. Further, an N2 gas supply source 34 is connected to the rinse liquid tank 35 via a regulator 32 and a filter 33, and the N2 gas supply source 34 supplies N2 gas.
The rinsing liquid R in the rinsing liquid tank 35 is sent to the supply nozzle 22 by being pressurized by the gas, and is supplied onto the wafer W.

In this way, by supplying the developing solution D and the rinsing solution R to the surface of the wafer W from the common supply nozzle 22 through the merging pipe 24, the developing solution D and the rinsing solution R are separately or mixed at the same position. It is possible to prevent uneven development due to the residue (scum) of the resist dissolved by the developing solution D.

On the other hand, a tip portion of a discharge pipe 39 is connected to the supply nozzle 22 at a position adjacent to the supply portion for the developer D and the rinse liquid R, and the discharge pipe 39 has three ports and two positions. An N2 gas supply source 34 or a trap tank 40 as gas-liquid separating means is connected via a switching valve 41. An ejector 43 (pneumatic vacuum device) is connected to the exhaust pipe 42 connected to the bubble removal port 40a at the upper part of the trap tank 40. In this ejector 43, for example, a compressed air injection nozzle 43b is inserted into an air chamber 43a connected to the exhaust pipe 42, and the injection nozzle 43b is also inserted.
Of the trap tank 40 by the Bernoulli effect by injecting the compressed air supplied from the compressed air supply source 44 connected to the injection nozzle 43b from the injection nozzle 43b. The air in the drainage liquid collected in the above can be discharged through the exhaust pipe 42. In this case, an opening / closing valve 45 is provided between the injection nozzle 43b of the ejector 43 and the compressed air supply source 44, and the trap tank 40 is controlled by controlling the operation of the ejector 43 by adjusting the opening / closing of the opening / closing valve 45. It is possible to prevent the drainage liquid from flowing into the exhaust pipe 42 side due to a negative pressure inside. A filter 4 is provided between the 3-port 2-position switching valve 41 and the N2 gas supply source 34.
6, mass flow controller 47 and regulator 32
Is installed. Further, an opening / closing valve 49 is provided in the drainage pipe 48 connected to the drain port 40b of the trap tank 40.

As described above, the exhaust pipe 42 is attached to the supply nozzle 22.
The N 2 gas supply source 34 and the ejector 43 are switchably connectable via the via, so that the supply nozzle 22 moves backward from the top of the wafer W and waits for the developer D or the rinse R to flow onto the wafer W. It is possible to prevent dripping and to clean the inside of the supply nozzle 22 by supplying N2 gas into the supply nozzle 22 after the processing.

Next, the operation of developing the wafer W having the circuit pattern transferred to the polyimide resist by using the developing apparatus having the above-described structure will be described with reference to FIG. First, the processing cup 21 is lowered to receive the exposed wafer W from the wafer transfer arm 10 of the wafer transfer mechanism 11 onto the spin chuck 20, and then the processing cup 21 is raised to accommodate the wafer W.
After that, the supply nozzle 22 is moved from the standby position to a position above the center of the wafer W by a moving mechanism (not shown), and the rinse liquid R is applied to the surface of the wafer W rotated by the drive of the spin chuck 20 for 1 to 2 seconds, for example, about 130 cc / minMAX. And a liquid film of the rinse liquid R is formed on the surface of the wafer W (pretreatment step). Next, the developing solution D is sprayed for about 60 seconds at, for example, 130 cc / min MAX for spray development (processing step). The rotation speed of the wafer W in the pretreatment process and the treatment process is about 1000 rpm. Then, about 3 seconds before the supply of the developing solution D is completed, the rinse solution R is supplied at, for example, 130 cc / min MAX (first post-processing step), and after the completion of the supply of the developing solution D, about 1
The rinse liquid R is supplied for 0 to 20 seconds (second post-treatment step). The number of rotations of the wafer W in the first and second post-processing steps is 1000 to 1500 rpm. When the developer D is supplied after the rinse R is supplied, the supply of the developer D is started before the end of the supply of the rinse R to make the rinse R
The developer D and the developer D may be overlapped (mixed supply) (see FIG. 5A). By doing so, the developer D can be supplied following the liquid film formed by the rinse R, and the spread of the developer D can be further smoothed.

As described above, the developing solution D and the rinsing solution R are supplied so as to hit the surface of the wafer W more strongly than in the case of a normal resist film, and the resist film is melted and scraped, and the melted product is positively pushed away. By doing so, for example, even when the resist film has a thickness of 10 μm, the development process can be performed in 60 seconds, which is 10 times higher than the development speed in the case of a normal resist film (film thickness: 1 μm is performed in 60 seconds). It can be developed at about double the speed. Since the line width of the circuit pattern of the polyimide-based resist is, for example, 3 μm, which is wider than the line width (0.5 μm) of the circuit pattern of the normal resist, the developer D and the rinse liquid R are strongly applied to the surface of the wafer W. There is no particular problem in the pattern forming process even if the film is removed by scraping.

FIG. 3 is a schematic block diagram of the second embodiment of the developing device according to the present invention. The second embodiment is a case where the timing and the supply amount when the rinse liquid and the developing liquid are overlapped (mixed supply) can be changed. That is, the developing solution supply pipe 26 and the rinse solution supply pipe 27
The opening and closing valves 50 and 51 are provided on the upstream side of the connecting portion of the merging pipe 24, and the supply timing and the supply amount of the developing solution D or the rinsing liquid R can be changed by the opening and closing operations of these opening and closing valves 50 and 51. This is the case. In addition,
Since the other parts of the second embodiment are the same as those of the first embodiment shown in FIG. 2, the same parts are designated by the same reference numerals and the description thereof will be omitted.

When the wafer W having the circuit pattern transferred to the polyimide-based resist film is developed by using the developing device of the second embodiment having the above-described structure, the rinse solution R is used.
When the supply of the developing solution D is started before the end of the supplying of the developing solution D, the opening / closing valves 50 and 51 are operated to gradually increase the developing solution D (for example, 1
The rinse solution R and the developing solution D can be overlapped (mixed supply) by increasing from 0 to 130 cc / min in about 2 seconds (see FIG. 5B).

About 3 before the end of the supply of the developer D.
When the rinse liquid R is supplied from a second before (in the first post-treatment step), the opening / closing valves 50 and 51 are operated to gradually decrease the supply amount of the developer D (for example, from 130 cc / min to 0 in 3 seconds). Decrease (see FIG. 6A) or gradually increase the rinse liquid R (for example, increase from 0 to 130 cc / min in 3 seconds).
(See FIG. 6B), or the developer D is gradually decreased (for example, from 130 cc / min to 0) and the rinse liquid R is gradually increased (for example, 0 to 130 cc / mi).
n) can be performed (see FIG. 6C).

As described above, by mixing and replacing the developing solution D and the rinsing solution R while gradually changing the concentrations, the developing solution D and the rinsing solution R, which are different liquids, can be mixed and supplied while eliminating the discomfort. Further, particularly when the supply of the developing solution D is started before the end of the supply of the rinse solution R, the concentration of the developing solution D is gradually increased by gradually increasing the developing solution D (for example, from 0 to 130 cc / min). Since the density can be increased, uniform development can be achieved.

In the above embodiment, the developing solution D and the rinsing solution R are supplied from the common supply nozzle 22 through the joining pipe 24 to the wafer W.
Although the case of supplying the developer to the surface has been described, the developer D and the rinse liquid R do not necessarily have to be supplied from the common supply nozzle 22, and for example, the developer supply of the same shape such that the same ejection pattern can be obtained. The nozzle and the rinse liquid supply nozzle may be arranged close to each other. Further, in the above embodiment,
The case where the developing solution D and the rinse solution R are supplied to the surface of the wafer W by the spray type supply nozzle 22 has been described, but a paddle type supply nozzle that discharges in a curtain shape may be used instead of the spray type supply nozzle 22. It is possible.

In the above embodiment, the case where the object to be processed is a semiconductor wafer has been described, but the object to be processed is not necessarily limited to the semiconductor wafer, and for example, an LCD substrate, a ceramic substrate or the like is processed. Is also applicable.

[0029]

In summary, according to the present invention, the following effects can be exhibited.

1) According to the processing method of claim 1, before supplying the processing liquid to the object to which the circuit pattern is transferred, a cleaning liquid is supplied to form a liquid film on the surface of the object. Since the spread of the treatment liquid can be promoted, the throughput can be improved. In addition, since the swelling and shrinkage of the resist of the circuit pattern formed on the object to be processed can be mitigated by mixing and replacing the processing liquid and the cleaning liquid, the yield can be improved.

2) According to the treatment method of claim 2, the concentration of the treatment liquid is increased by gradually increasing the treatment liquid to a predetermined amount within a time when the supply of the cleaning liquid and the supply of the treatment liquid in the treatment process overlap. Can be gradually increased,
In addition to the above 1), the processing can be made uniform and the yield can be improved.

[Brief description of drawings]

FIG. 1 is a perspective view of a resist coating and developing processing system incorporating a processing apparatus according to the present invention.

FIG. 2 is a schematic configuration diagram of a first embodiment of a processing apparatus according to the present invention.

FIG. 3 is a schematic configuration diagram of a second embodiment of the processing apparatus according to the present invention.

FIG. 4 is a timing chart of the processing method of the present invention.

FIG. 5 is a timing chart showing another state of overlap between the pretreatment step and the treatment step in the treatment method of the present invention.

FIG. 6 is a timing chart showing another state of the first post-treatment step in the treatment method of the present invention.

[Explanation of symbols]

 22 Supply Nozzle 24 Confluence Pipe 25 Three-way Switching Valve 26 Developer Solution Supply Pipe 27 Rinsing Solution Supply Pipe 34 N2 Gas Supply Source 50,51 Open / Close Valve W Wafer (Processing Object) D Developing Solution (Processing Solution) R Rinsing Solution (Cleaning Solution)

Claims (6)

[Claims] 1. A treatment method of supplying a treatment liquid to a treatment target to which a circuit pattern is transferred to perform treatment, comprising a pretreatment step of supplying a cleaning liquid to the treatment target, and a step of supplying the treatment liquid to the treatment target. A treatment step of supplying the treatment liquid to the treatment object; a first post-treatment step of mixing the treatment liquid and the cleaning liquid and supplying the treatment liquid to the treatment object before the supply of the treatment liquid is completed; A second post-treatment step of supplying a cleaning liquid to the object to be treated after the supply of the mixed liquid; 2. A treatment method of supplying a treatment liquid to a treatment object to which a circuit pattern has been transferred to perform treatment, and a pretreatment step of supplying a washing liquid to the treatment object, and supplying before the completion of the supply of the washing liquid. And a first post-treatment step of supplying a treatment liquid to the object to be treated, mixing the treatment liquid and the cleaning liquid before the end of the supply of the treatment liquid, and supplying the mixture to the object to be treated, A second post-treatment step of supplying a cleaning liquid to the object to be processed after supplying the mixed liquid of the processing liquid and the cleaning liquid. 3. The processing method according to claim 2, wherein the processing liquid is gradually increased to a predetermined amount within a time period in which the supply of the cleaning liquid and the supply of the processing liquid overlap in the processing step. 4. The treatment method according to claim 1, wherein the treatment liquid is gradually reduced in the first post-treatment step. 5. The treatment method according to claim 1, wherein the cleaning solution is gradually increased in the first post-treatment step. 6. The treatment method according to claim 1, wherein in the first post-treatment step, the treatment liquid is gradually decreased and the cleaning liquid is gradually increased.